Late Anisian radiolarian assemblages from the Yarlung‐Tsangpo Suture Zone in the Jinlu area, Zedong, southern Tibet: Implications for the evolution of Neotethys. (5th April 2019)

• Record Type: Journal Article
• Authors: Chen, Dishu; Luo, Hui; Wang, Xueheng; Xu, Bo; Matsuoka, Atsushi
• Is Part Of: Island arc. Volume 28:Number 4(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-04-05
• Subjects: biostratigraphy -- Neotethys -- radiolaria -- Tibet -- Triassic -- Yarlung‐Tsangpo Suture Zone; Plate tectonics -- Periodicals; Island arcs -- Periodicals; Geodynamics -- Periodicals; 551.136
• DOI: 10.1111/iar.12302
• Languages: English
• ISSNs: 1038-4871

Abstract

Abstract: Abundant Triassic radiolarian fossils were obtained from varicolored bedded cherts exposed in the Buruocang section near Jinlu village, Zedong, southern Tibet. The radiolarian‐bearing rocks represent fragmented remnants of the Neotethys oceanic sediments belonging to the mélange complex of the east part of the Yarlung‐Tsangpo Suture Zone. Two new middle Late Anisian radiolarian assemblages recognized from this section named Oertlispongus inaequispinosus and Triassocampe deweveri, respectively, are compared with those known from Europe, Far East Russia, Japan, and Turkey. These Anisian radiolarian fossils are the first reported in southern Tibet and the oldest radiolarian record within the Yarlung‐Tsangpo Suture Zone. They improve time constraints for the evolution of Neotethys in southern Tibet. Abstract : Two new middle Late Anisian radiolarian assemblages recognized from this section named Oertlispongus inaequispinosus and Triassocampe deweveri, respectively, are compared with those known from Europe, Far East Russia, Japan, and Turkey. These Anisian radiolarian fossils are the first reported in southern Tibet and the oldest radiolarian record within the Yarlung‐Tsangpo Suture Zone. They improve time constraints for the evolution of Neotethys in southern Tibet. Abstract : 豊富な三畳紀放散虫化石が，チベット南部Zedong Jinlu村近郊のBuruocangセクションに露出する多色層状チャートから得られた. 含放散虫岩は，ヤールン‐ツァンポー縫合帯東部のメランジュコンプレックスに属するネオテチス海堆積物の一部を代表する. 本セクションから新たに得られたアニシアン新世中期の2つの群集，すなわち Oertlispongus inaequispinosus 群集と Triassocampe deweveri 群集は，ヨーロッパ，極東ロシア，日本，トルコから知られている群集に比較される. これらのアニシアン放散虫化石の報告はチベット南部からは初めてであり，ヤールン‐ツァンポー縫合帯における最古の放散虫記録である. これらの産出記録は，ネオテチスの進化について，より確かな年代的制約を与えるものである.